cos(90+a)cos(180-a)[tg(180+a)+tg(270-a)] Помогите,пожалуйста. - №22099992

cos(90+a)cos(180-a)[tg(180+a)+tg(270-a)]
Помогите,пожалуйста.
- Предмет:
  Алгебра
- Автор:
  xzavier
- 6 лет назад

Ответы 1

=-sina *(-cosa)*(tga+ctga)= sina*cosa( sina/cosa - cosa/sina)== sina*cosa( (sin²a+cos²a / sinacosa))= sin²a +cos²a=1
- Автор:
  audreymitchell
- 6 лет назад
- 0
Добавить свой ответ

Еще вопросы

Y=5x+1
x= -2
x=1
x=0
Найти значение х когда известен y
y=0 и y=6
и если можно то формулу для нахождения х когда известен y
- Предмет:
  Математика
- Автор:
  desiraecooley
- 6 лет назад
- Ответов:
  
  1
- Смотреть
3(x+y)(x-y)-(x-y)2
Два в конце- это квадрат.
Разложить на множители
И если можно, обьясните
- Предмет:
  Алгебра
- Автор:
  izabella
- 6 лет назад
- Ответов:
  
  1
- Смотреть
Почему люди должны уважать религии друг друга?
- Предмет:
  Русский язык
- Автор:
  jasminepratt
- 6 лет назад
- Ответов:
  
  4
- Смотреть
Сопоставьте заголовки и тексты:

A. The creator of the Christmas card
D. The ancestor of the Christmas card
B. The place of creation
E. What are Christmas cards like?
C. Displeasure of some people
F. Christmas cards for children

1. Today, we send millions of Christmas cards every year. But in fact the Christmas card is a relatively modern
invention. In the Middle Ages, European wood engravers produced prints with religious themes. But the first real
Christmas card, as we understand the term today, was designed in London, England in 1840. It went on sale in 1843.
2. The designer was John Callcott Horsley, a well known British painter and member of the Royal Academy. He
designed the card at the suggestion of his friend Sir Henry Cole, who was the first director of the Victoria & Albert
Museum. Horsley produced 1,000 cards and offered them for sale at Is (one shilling) each.
3. They were printed on stiff card and coloured by hand, with the greeting: «A Merry Christmas and a Happy New
Year to You». The card showed three pictures: in the centre, a family party; to one side the hungry receiving food; to
the other side the poor being clothed. Puritans immediately denounced the card, since it showed people drinking in
the family party. But with most people the idea was a great success and the Christmas card quickly became very
popular.
4. Christmas cards were not the first greetings cards. Since 1796, with the improvements in printing, merchants had
been sending cards to their customers offering «best wishes» for the New Year. In many countries, Christmas cards
gradually became even more popular than New Year's cards.
5. As Christmas is the birthday of Jesus Christ, cards often show scenes of his nativity. Others show images
associated with Christmas such as wintry scenes of snow-laden pines, Father Christmas (Santa Claus), stars, candles
or holly. The traditional greeting written on a Christmas card is «Merry Christmas», but many other greetings are also
used, such as «Happy Xmas» or «Happy Noel».
- Предмет:
  Английский язык
- Автор:
  bonnieford
- 6 лет назад
- Ответов:
  
  4
- Смотреть

How much to ban the user?

1 hour 1 day 100 years